Stoker drive



June 18, 1940. w. w. PECK 2,204,768

STDKER DRIVE Filed Jan. 18, 1937 2 Sheets-Sheet 1 w. w.- PE CK 2,204,768

sToKER DRIVE Filed Jan. 18, 1937 2 Sheets-Sheet 2 Patented June 18, 1940UNITED STATES grants PATENT VOFFECE 7 Claims.

This invention relates to stoker and other drives and is concerned moreparticularly with a drive of the intermittent type. 1

It is an object of the invention to provide an improved mounting for arace or shell of a roller clutch or bearing.

It is another object of the invention to provide improved roller cageand cam construction for one-Way clutches and brakes.

It is a further object of the invention to provide an improved infiniteadjustment of the rate of feeding of fuel by a stoker or the like.

It is also an object of the invention to afford means for readydetermination of the rate at which a stoker or the like feeds conveyedmaterial.

A further object of the invention resides in the provision of a readilyvisible means displaying information as to the rate at which the deviceis feeding the material conveyed.

Further objects and advantages of the invention will appear as thedescription proceeds.

The inventiomin a preferred form, is illustrated in the accompanyingdrawings and hereinafter fully described.

Figure 1 is a fragmentary transverse sectionelevation of a stoker driveembodying the invention.

Figure 2 is a section-elevational view showing details of the brake ornoback construction of the invention.

Figure 3 shows a ratchet roller cage appearing in end elevation inFigure 2.

Figure 4 is a fragmentary sectional view taken substantially asindicated by the line IV-IV in Figure 1. I

Figure 5 is a broken transverse sectional hybrid view showing featuresof both the clutc and brake of the ratchet mechanism.

Figure 6 is a broken plan- View of the feedadjusting and indicatingmechanism appearing at the upper parts of Figures 1 and l.

Referring now more particularly to the drawings, which illustrate forexemplary purposes part of a coal stoker installation, the coal conveyortube I, adapted atone end to communicate with a retort located at thefirebox' of a furnace or boiler (not shown), is disposed about afeedscrew 2 having a polygonal socket 3 adapted to receive thecorrespondingly shaped end 4 of the screw actuating shaft 5, adapted tobe rotated manually by the application of a wrench or other suitabletool at 6, or to be power driven by transmission mechanism embodying theinvention and suitably encased within the housing 1. Suitablecommunication is. afforded. for the passage of combustion-supporting airfrom a blower 8 or the like to the retort.

Journaled in the housing I is a driven wheel Worm 9 arranged to drive aworm wheel it which is rotatably mounted on the shaft 5. The wheel itcarries a cam II engageable by a follower I? which is preferably springpressed as shown at l3 into yielding engagement with the cam and whichcomprises a lever pivoted to the housing at l4.

A pivot link I5 having a crank connection at [6 with the follower and atI! with the shell it of a one-way driving clutch ill effectsintermittent rotary motion of the shell in response to continuingrotation of the cam.

The shell [8 encircles rollers 20 which are disposed about the forwardperiphery 2| of the inner race or hub 22 splined or otherwise drivablyconnected to the shaft 5. The hub 22 extends laterally beyond the shell!3 to provide a rear hub periphery 23 of a second, oppositely operatingone-way roller noback device or brake indicated generally at 24. Brakerollers 25 are disposed about the hub portion 23 and are in turnsurrounded by the shell or outer race 26. The brake 24 thus provides ameans for preventing backlash of the shaft 5 between driving strokes ofthe shell ill of the driving clutch it. Instead of employing relativelylong and short rollers for the clutch and noback, I provide a pluralityof drive rollers of the same size as the noback rollers, thus doing awaywith the need for different roller sizes.

A salient feature of the invention involves the ratchet orclutch-and-brake construction. The hub 22 has its outer surfacepreferably formed with facets in a regular polygonal series and is thusmore simple than hubs of other clutch and noback constructions.

A roller cage 29 carries lugs 30 which are passed through correspondingholes 3i in end plates 32 and then riveted or headed over as at 33 toprovide a unit-whereby the rollers are held in proper cooperativerelation with the hub 22 and the shells l8 and 26. A spacer ring 3dholds the rollers of the clutch and brake apart.

A spring 35 such as a torsion spring in the form of a split ring isemployed to yieldab-ly urge the rollers into wedging engagement with therespective facets of the hub 22 and the curved surface 36 of the shellI8 or curved surface 3'! of the shell 26, as the case may be. Eachspring ring has an end 38 anchored to the hub 22 and another end 39offset outwardly and extending through a slot 40 in the retainer sleeve,the arrangement being such that the springs exert equal pressure so asto oppose biasing of the rollers, while urging all of the rollers in thesame direction. It will be observed that the driving shell I8 turns in adirection to wedge the rollers 20 between it and the hub 22 and thusdrives the latter, which drives the shaft 5. The hub 22, turning in thedirection in which the rollers 25 are spring pressed, tends to draw awayfrom the rollers 25, the shell 26 being held against turning by theball-end 4| of the stud 42 fitting in the socket 43 in said shell. Thusthe shell 26 does not interfere with rotation of the hub 22. When,however, the hub 22 tends to reverse its direction of movement at thecompletion of its driving stroke, that is, to have a back lash motion,the rollers 25 tightly wedge between the shell 22 and the hub 22,thereby instantly preventing such retrograde motion of the latter.

The advantages of the universal connection between the shell 26 and thestud 42 will be manifest when it is considered that any burrs ornon-uniformity or irregularity in the engaging surfaces of the variousparts included and associated with the clutch and/or brake structuretend to cant or bias the rollers so as to interfere with properoperation of the ratchet mechanism. The ball and socket arrangementenables the brake shell 26 to assume, by hunting, any position withoutinterference with the ball stud so that the shell will adapt itself tothe proper c0- operative relation with the remaining structure includingthe rollers, as the conditions of assembly and operation may require.

The cam ll, follower l2 and the driving connection between the clutchshell l8 and the follower are so designed as to effect a drive of theshaft 5 and consequently of the feed screw 2 at substantially uniformrotary speed upon each stroke.

Inasmuch as the brake shell 28 is held stationary by the stud 42, itwill be observed that, during the driving portion of the rotation of thecam H, the clutch shell 18 will be turned as indicated by the arrow 45,for example, and, due to the load resistance offered by the hub 22 andthe fact that the rollers 20 are urged by the springs 35 in the samedirection as the clutch shell l8, as indicated by the arrow 46, therollers 20 are wedged tightly between the shell l8 and the hub 22 so asto cause the later to be driven by the shell 18. During this time, therollers 25 are urged by the springs 35 in the direction of rotation ofthe hub 22, as shown by the arrow 47, the hub tending to occupy areleased position relative to the rollers 25, so that the hub turnsfreely independently of the brake shell 26.

However, during the return stroke of the clutch shell l8, it will bereadily appreciated that the rollers 26 will be in non-obstructingrelation to the shell l8 and hub 22, the latter being wedged against therollers 25 upon any tendency of the hub to turn in the reversedirection, Accordingly it is evident that the brake shell 26instantaneously and positively prevents backlash of the hub 22 withoutresisting the return stroke of the clutch shell l8, and also permitsfree driving movement of the shell I8 and hub 22 With this ratchetconstruction I am enabled to employ an inner race of extreme simplicity.The leading facet portions 59 of the clutch portion of the hub 22cooperate with the associated clutch rollers 20 and clutch shell 18 toprovide a driving connection whereby the hub is driven by the shell. Theleading facet portions 5i of the brake portion of the hub likewisecooperate with the brake rollers 25 and the brake shell 26 to provide awedging engagement so as to prevent reverse movement of the hub. The hubthus lends itself to simple and economical manufacture withoutrequirement of the machining of special curves for roller-wedgingpurposes.

The top or cover plate 52 of the transmission housing 1 carries aslidable bar 53 in a housing 53a. The bar serves as a stop to limit thereturn of the cam follower l2 and thereby adjusts the throw or length ofstroke of the follower in response to movement of the cam II. This iseffected by fixing on the pivot shaft M a collar 54 having a lug or boss55 whose path of rotation may be obstructed by the bar. The side of thebar engageable with the lug is tapered at 56 so that by adjusting thebar transversely of the plane of rotation of the lug, the lug may bestopped by the bar at different points. This tapered edge may becalibrated as shown at 5! to indicate visually the rate of feed in, say,pounds per hour according to the proximity of the lug edge 58, forexample, to the nearest graduation.

The height of the incline of the bar is preferably such that in onelimiting position the follower is located out of the path of the cam llso as to be unaffected by the cam, and in such event the feed screw isstationary. When the bar is so adjusted as not to interfere with thelug, the follower and consequently the feed screw receives its maximumlength stroke, determined by the maximum throw of the cam. A thumb screw59 or the like may be employed to hold the sliding bar in any of aninfinite number of adjustments. care of the largest home or the smallestcottage, and in one installation which has been received with favor bythe trade the unit is capable of feeding from 50 lbs. per hour down to apound or less per hour. This invention accordingly obviates the need foremploying units of different sizes such as would be necessary where oneinstallation has only a few pounds per hour capacity and a differentinstallation is required for a substantially larger capacity,

I claim:

1. In a stoker drive mechanism, a feed screw drive shaft, power drivemeans including a driven oscillating member, means associated with saidoscillating member and with said drive shaft for translating oscillatorymovement of said oscillatmg member to intermittent rotative movement ofsaid drive shaft, a stop member on said oscillating member adapted tomove through an arc during oscillation of said member, and an adjustableabutment for said stop member, including a bar mounted for longitudinalsliding movement along an axis inclined angularly at an angle other than90 relative to the plane of said arc, said bar having a surfaceperpendicular to the plane of said are, comprising an abutment surfacefor said stop, whereby movement of said bar along its longitudinal axismay shift the position of said abutment surface with respect to saidstop mem ber thus to vary the amplitude of oscillatory movement of saidoscillating member.

2. In an intermittent drive mechanism, a housing, driving and driventorque transmitting members, an overrunning clutch adapted to establisha one-way driving connnection with said driven member, means driven bythe driving member for oscillating an element of said overrunningclutch, a one way break for preventing reverse movement of the drivenmember, said brake including a hub connected to the driven The unit maybe employed to take member, a shell encircling said hub, rollersinterposed between said shell and hub, and means anchoring said shell tosaid housing comprising a universal joint connection between the shelland housing permitting the shell to be self-aligning with respect to thehub and rollers.

3. In an intermittent drive mechanism, a housing, driving and driventorque transmitting members, an overrunning clutch adapted to establisha one-way driving connection with said driven member, meansdriven by thedriving member for oscillating an element of said overrunning clutch,manually adjustable stop means for controlling the amplitude ofoscillation of said element, a one way brake for preventing reversemovement of the drivenmember, said brake including a hub connected tothe driven member, a shell encircling said hub, rollers interposedbetween said shell and hub, and means anchoring said shell to saidhousing comprising a universal joint connection between the shell andhousing permitting the shell to be self-aligning with respect to the huband rollers.

l. In an intermittent drive mechanism, a housing, driving and driventorque transmitting members, an overrunning clutch adapted to establisha one-way driving connection with said driven member, means driven bythe driving member for oscillating an element of said overrunningclutch, and a one way brake for preventing reverse movement of thedriven member, said brake including a hub connected to the drivenmember, a shell encircling said hub, clutch rollers interposed betweensaid shell and a hub, and means anchoring said shell to said housingcomprising a stop member fixed in the housing and having a sphericalhead, and a fork on the shell embracing said head, said anchoring meanspermitting the shell to be self-aligning with respect to the hub androllers.

'5. In an intermittent drive mechanism, drivmovement of the lever, and alink pivoted at one end to an intermediate region of the lever and atits other end to said first mentioned clutch element so as to transmitoscillating movement thereto from the lever.

6. In an intermittent driven mechanism, driving and driven torquetransmitting members, an overrunning clutch for transmitting drive tosaid driven member, said clutch including an element connected to saiddriven member and another element which is adapted to be oscillated, andmeans for effecting the oscillation of said oscillatable elementcomprising a lever, a support to which one end of the lever is pivoted,eccentric means driven by the driving member, and cooperating with theother end of the lever for swinging the lever about its pivotalconnection to the support, and a link connecting said oscillatableclutch element with an intermediate region of said lever fortransmitting oscillating movement from the lever to said oscillatableelement.

7. An intermittent drive mechanism as defined in claim 5, includingadjustable stop means for limiting the return movement of the leverwherebyto limit the extent of oscillation of the clutch element,

WILLIAM W. PECK.

